TOKYO - At her first job in Tokyo in the 1970s, Ms Yukako Uchinaga hid in the ladies' room every day at 8pm while an inspector made sure all female employees had gone home. Then she came out and put in more hours. "My boss used to say, 'I don't want to be put in jail'," said Ms Uchinaga, chief executive officer at Berlitz, a global leadership training and education company. She was referring to a labour law that capped women's overtime at two hours a day. "I complained it was unfair, like being in a 100-metre race with my hands and feet tied while all my male colleagues ran freely." Four decades after Ms Uchinaga played hide and seek with the now-defunct law as an IBM systems engineer, women occupy just 1 in 70 management positions at Japanese companies. Promoting women would help companies be more diverse and break the "salaryman monoculture" that hinders change and growt...